Re: CCTV with Cat5 and what I've learned.

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On Friday, January 18, 2013 7:36:21 AM UTC-5, NickMark wrote:
> On Friday, January 18, 2013 12:21:16 AM UTC-5, Jim wrote:
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> > A few weeks ago I mentioned that I was doing my first CCTV install usin=
g Cat5 and Baluns. I think it was here (but maybe in other groups too) that=
 it was touted as being less expensive to use Cat5 and Baluns compared to C=
oax Siamese etc.=20
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> > This is what I learned:
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> > 12 cameras in a warehouse. Cameras draw 800ma max. Contrary to what the=
 Balun people say their products will do ..... doing the calculations mysel=
f,(wire size, number of conductors, voltage drop, etc)theycouldn't/wouldn't=
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> > "guarantee" that the cameras would work at the distances their advertis=
ing said they would. Their estimates of video distance was not my concern b=
ut they had no idea that the Baluns could not carry camera "power" over the=
 same distance. Since there are no outlets in the back of the warehouse (wh=
ere most of the cameras are located) I had to use 24VAC supply with 1- amp =
output each channel because there was more than a 10% voltage drop at the f=
urthest camera if I used 12VDC. $200.00 for power supply. Max safest distan=
ce to keep cameras at less than 10% voltage drop is somewhere around 150 to=
 200 feet. In order to do this, I had to inquire with the Balun mfgs/suppli=
ers, how many of the Cat5 pairs were  used to carry power. No one that I ta=
lked to knew. They "assumed" two pair were used for video and two pair for =
power. Two pair for power would not stay within voltage drop spec at 168fee=
t. (my furthest run) So, I located Baluns with screw terminal connections, =
so I could use three Cat 5 pairs for power and one pair for video. So that =
elimiated using Baluns with RJ45 connectors and required more time to untwi=
st, strip, twist pairs and connect wires to termials, then it would take to=
 crimp an RJ45 connector for plugging into a RJ45 Balun. 12 Baluns @ $16.00=
 each plus shipping.
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> > I also had to locate Baluns that had the power and video in/outputs on =
flying leads, because the Baluns with the BNC connectors attached would not=
 all fit on the back of a 16 channel DVR if they had to be plugged directly=
 into the connectors on the back of the DVR. But THEN .... even though you =
have flying leads, you also cannot have 12 Baluns hanging off of the back o=
f a DVR by 6 inch leads. They have to be mounted elsewhere, out of sight. (=
I didn't think of this until later) When using Siamese coax, you just have =
to strip the power wires back and re-route them to the power supply and con=
nect them directly to the terminals in the power supply and then continue t=
he coax runs to the DVR and and crimp BNC's on them. When using the Baluns =
the Cat5 has to be run to where the Baluns are going to be located and untw=
isted, stripped, twisted in pairs and attached to the screw termials on the=
 Baluns. Then, using the hard wire adapter power plugs, it's necessary to r=
un additional wires from the Baluns back to the power supply. But now, sinc=
e the Baluns are located "away" from the back of the DVR, it is necessary t=
o manufacture BNC jumper cables from the video output of the Baluns to run =
between the location of the Baluns to the back of the DVR.
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> > Behind the desk, mounted to the wall is a 12 x 12 x 4 inch plastic "juc=
tion" box containing the Baluns $15.00. Out of this box runs a group of pow=
er cables from the power supply (mounted next to the plastic junction box.)=
 a group of Cat5 cables from the cameras and a group of BNC jumper cables g=
oing to the back of the DVR. BNC connectors 12X2 @ .59each $15.00
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> > I don't know if I'm missing something (?) I don't know if I've gone ove=
rboard (?) but from what I see, with the additional parts and labor there's=
 no F....ing way it's cheaper to do a Cat5 with Baluns CCTV job compared to=
 a siamese wire job.=20
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> > Comments please?
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> Thats all I run is cat 5 and baluns on CCTV jobs any more like dawson sai=
d matter of finding right combo of parts for job

I agree with these 2 Jim.=20
What I might have done is run as many cat5's as needed JUST FOR VIDEO for a=
ll cams, then run ONE 18awg or larger from front to back of warehouse and m=
ount the power supply up front and use the 18awg to transfer power to the r=
ear and terminate it in a breakout box of some kind where you can then run =
"Local" power to each cam from your breakout box. Keeps the power run under=
 control on heavier wire, no interference on video from power run in same c=
able jacket, and less over all cat5 cables to run.